Trish -
generally speaking Colourblindness skips a generation,

It is a gene that is carried on the X chromosome on the (maternal side) and often passed to males.
(female colourblindness is less common than males for this reason.

So you have a good chance there will be no colourblindness in your DS as your DH would have passed on his Y chromosome and not the X carrying colourblindness gene to your son ( i hope this makes sense).

However your DH can pass the X chromosome onto his daughters who will often dormantly carry it until they have children.